import turtle


window = turtle.Screen()
window.bgcolor("red")


def draw_square():
    t = turtle.Turtle()
    t.shape("turtle")
    t.speed(2)

    for i in range(4):
        t.forward(100)   # 向前移动100单位
        t.right(90)     # 右转90度


def draw_tri():
    t = turtle.Turtle()

    window = turtle.Screen()
    for i in range(3):
        t.forward(100)
        t.right(120)

def draw_circle():
    DEGREE = 10
    t = turtle.Turtle()
    t.speed(100)
    for i in range(360 // DEGREE):
        t.right(DEGREE)
        for i in range(4):
            t.forward(100)   # 向前移动100单位
            t.right(90)     # 右转90度


# draw_square()
# draw_tri()
draw_circle()

window.exitonclick()